MULTIPLEXER AND METHOD FOR DRIVING THE SAME
A multiplexer is provided herein. The multiplexer has a plurality of first driving units and a plurality of second driving units. Each of the first driving units has a first data voltage input terminal, and each of the second driving units has a second data voltage input terminal. The first data voltage input terminal and the second data voltage input terminal are configured to receive pixel voltage signals with different polarities. In the first driving unit, a voltage difference between a gate and a drain of a transistor is controlled by a first reset signal, wherein the transistor of the first driving unit is coupled to the first data voltage input terminal and a first data line. In the second driving unit, a voltage difference between a gate and a drain of a transistor is controlled by a second reset signal, wherein the transistor of the second driving unit is coupled to the second data voltage input terminal and a second data line.
The present invention relates to a multiplexer and a method for driving the same, and specifically, to a multiplexer comprising single-type transistors and a method for driving the same.
BACKGROUND ARTIn the current display panel technology, because a low temperature poly-silicon (LTPS) thin film transistor (TFT) has a high mobility and high reliability, the panel can have a high aperture ratio, and a circuit of a multiplexer can be formed on a substrate, so as to reduce the number of source driver ICs, and satisfy high specification panel design requirements. In addition, during the operation of the panel, because a polarity reversal operation needs to be performed on sub-pixels of the panel, the polarity of a Gamma voltage received by each of the sub-pixels in each frame period may be a positive polarity or a negative polarity. In the case where the polarity reversal operation needs to be performed on the sub-pixels, a traditional multiplexer fabricated by using single-type transistors such as N-type metal-oxide-semiconductor (NMOS) transistors or P-type metal-oxide-semiconductor (PMOS) transistors may have different driving capabilities for the sub-pixels when receiving Gamma voltages of different polarities. Therefore, complementary metal oxide semiconductor (CMOS) transistors are traditionally adopted to produce the multiplexer in a display.
However, compared with a circuit using purely NMOS transistors or PMOS transistors, a circuit using CMOS transistors requires a relatively complicated process and a larger number of masks, causing a significant increase in manufacturing costs of the panels fabricated with the CMOS process, which in turn is less welcome from the consumers' perspective.
SUMMARY OF THE INVENTIONIn view of this, the present invention provides a new multiplexer and a method for driving the same, so that the multiplexer has a sufficient driving capability for data lines and sub-pixels no matter whether the multiplexer uses NMOS transistors or PMOS transistors.
One embodiment of the present invention provides a multiplexer. The multiplexer includes a plurality of first driving units and a plurality of second driving units. Each of the first driving units includes a first data voltage input terminal, a first capacitor, a first transistor, and a second transistor. The first data voltage input terminal is configured to receive a first pixel voltage signal. The first capacitor includes a first terminal and a second terminal. The first terminal of the first capacitor is configured to receive a first switch signal. The first transistor includes a first terminal coupled to the second terminal of the first capacitor, a second terminal configured to receive a first reset signal, and a control terminal configured to receive a second switch signal. The first switch signal and the second switch signal have opposite phases. The second transistor first terminal coupled to the first data voltage input terminal a second terminal coupled to a first data line, and a control terminal coupled to the second terminal of the first capacitor. Each of the second driving units includes a second data voltage input terminal, a second capacitor, a third transistor, and a fourth transistor. The second data voltage input terminal is configured to receive a second pixel voltage signal, wherein the second pixel voltage signal and the first pixel voltage signal have opposite polarities. The second capacitor includes a first terminal and a second terminal. The first terminal of the second capacitor is coupled to the first terminal of the first capacitor, and is configured to receive the first switch signal. The third transistor includes a first terminal coupled to the second terminal of the second capacitor, a second terminal configured to receive a second reset signal, and a control terminal coupled to the control terminal of the first transistor to receive the second switch signal. The fourth transistor includes a first terminal coupled to the second data voltage input terminal, a second terminal coupled to a second data line, and a control terminal coupled to the second terminal of the second capacitor. The first reset signal is different from the second reset signal.
One embodiment of the present invention provides a multiplexer. The multiplexer includes a plurality of first driving units and a plurality of second driving units. Each of the first driving units includes a first data voltage input terminal, a first transistor, a second transistor, a third transistor, a fourth transistor, and a first capacitor. The first data voltage input terminal is configured to receive a first pixel voltage signal. The first transistor includes a first terminal, a second terminal, and a control terminal. The first terminal of the first transistor is configured to receive a first system voltage. The control terminal of the first transistor is configured to receive a first switch signal. The second transistor includes a first terminal coupled to the second terminal of the first transistor, a second terminal configured to receive a second system voltage, and a control terminal configured to receive a second switch signal. The first switch signal and the second switch signal have opposite phases. The third transistor includes a first terminal, a second terminal, and a control terminal. The first terminal of the third transistor is coupled to the first data voltage input terminal, and the second terminal of the third transistor is coupled to a first data line. The fourth transistor includes a first terminal coupled to the control terminal of the third transistor, a second terminal configured to receive a first reset signal, and a control terminal configured to receive a second switch signal. The first capacitor includes a first terminal coupled to the second terminal of the first transistor and the first terminal of the second transistor, and a second terminal coupled to the control terminal of the third transistor and the first terminal of the fourth transistor. Each of the second driving units includes a second data voltage input terminal, a fifth transistor, a sixth transistor, a seventh transistor, an eighth transistor, and a second capacitor. The second data voltage input terminal is configured to receive a second pixel voltage signal, wherein the second pixel voltage signal and the first pixel voltage signal have opposite polarities. The fifth transistor includes a first terminal, a second terminal, and a control terminal. The first terminal of the fifth transistor is configured to receive the first system voltage, and the control terminal of the fifth transistor is configured to receive the first switch signal. The sixth transistor includes a first terminal coupled to the second terminal of the fifth transistor, a second terminal configured to receive the second system voltage, and a control terminal configured to receive the second switch signal. The seventh transistor includes a first terminal, a second terminal, and a control terminal. The first terminal of the seventh transistor is coupled to the second data voltage input terminal. The second terminal of the seventh transistor is coupled to the second data line. The eighth transistor includes a first terminal coupled to the control terminal of the seventh transistor, a second terminal configured to receive the second reset signal, and a control terminal configured to receive the second switch signal. The second capacitor includes a first terminal coupled to the second terminal of the fifth transistor and the first terminal of the sixth transistor, and a second terminal coupled to the control terminal of the seventh transistor and the first terminal of the eighth transistor. The first reset signal is different from the second reset signal.
One embodiment of the present invention provides a method for driving the multiplexer described above. The multiplexer is used in a display, and all the transistors of the first driving unit and the second driving unit are N-type metal-oxide-semiconductor transistors. The method includes: during the nth frame period of the display, making the first pixel voltage signal to have a first polarity; making the second pixel voltage signal to have a second polarity; making the first reset signal to have an electric potential at a first rest level; and making the second reset signal to have an electric potential at a second reset level; wherein n is a positive integer, the first polarity is different from the second polarity, and the second reset level is higher than the first reset level; and during the (n+1)th frame period of the display, making the first pixel voltage signal to have the second polarity, making the second pixel voltage signal to have the first polarity, making the first reset signal to have the electric potential at the second reset level, and making the second reset signal to have the electric potential at the first reset level.
One embodiment of the present invention provides a method for driving the multiplexer described above. The multiplexer is used in a display, and all the transistors of the first driving unit and the second driving unit are P-type metal-oxide-semiconductor transistors. The method includes: during the nth frame period of the display, making the first pixel voltage signal to have a first polarity; making the second pixel voltage signal to have a second polarity; making the first reset signal to have an electric potential at a first reset level; and making the second reset signal to have an electric potential at a second reset level; wherein n is a positive integer, the first polarity is different from the second polarity, and the second reset level is higher than the first reset level; and during the (n+1)th frame period of the display, making the first pixel voltage signal to have the second polarity, making the second pixel voltage signal to have the first polarity, making the first reset signal to have the electric potential at the second reset level, and making the second reset signal to have the electric potential at the first reset level.
Through the embodiments of the present invention, two different reset signals are applied to the multiplexer to increase an absolute value of a voltage difference between a gate and a drain of a transistor for driving a data line, thereby strengthening the driving capability of the transistor. In this way, no matter whether the transistors of the multiplexer are NMOS transistors or PMOS transistors, the multiplexer has a sufficient driving capability for data lines and sub-pixels. Therefore, all the transistors of the multiplexer can either be N-type metal-oxide-semiconductor transistors or P-type metal-oxide-semiconductor transistors, thereby simplifying the process of manufacturing the multiplexer and/or a panel and improving the competitiveness of products thereof.
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In addition, the waveforms of the switch signals SWR, SWG, SWB, XSWR, XSWG, and XSWB, for example, are not associated with the polarities of the sub-pixels. In other words, the waveforms of the switch signals SWR, SWG, SWB, XSWR, XSWG, and XSWB remain unchanged in different frame periods F[+] and F[−]. However, the electric potential of the reset signal MUX_L1, the electric potential of the reset signal MUX_L2, the electric potential of the pixel voltage signal S2, and the electric potential of the pixel voltage signal S2 are associated with the polarities of the sub-pixels. For ease of description, it is assumed that the electric potentials of the pixel voltage signal S1 during the frame periods F[+] and F[−] are equal to a positive polarity pixel voltage +Vp and a negative polarity pixel voltage −Vp respectively; and the electric potentials of the pixel voltage signal S2 during the frame periods F[+] and F[−] are equal to the negative polarity pixel voltage −Vp and the positive polarity pixel voltage +Vp respectively, wherein Vp is greater than zero. In addition, as shown in
During, the frame period F[+], when the electric potential of the switch signal SWR is equal to the gate low potential VGL, and the electric potential of the switch signal XSWR is equal to the gate high potential VGH, the transistors T1 and T3 are both turned on, such that the reset signals MUX_L1 and MUX_L2 are transmitted to the gates of the transistors T2 and T4 respectively. In this case, because the electric potentials of the reset signals MUX_L1 and MUX_L2 are the reset levels Lv1 and Lv2 respectively, biases of the reset levels Lv1 and Lv2 are applied to the respective gates of the transistors T2 and T4, so that the transistors T2 and T4 are not turned on. In this case, the voltage differences between the two terminals of the capacitor C1 and between the two terminals of the capacitor C2 are (VGL−Lv1) and (VGL−Lv2) respectively. In
Similarly, during the frame period F[−], when the electric potential of the switch signal SWR is equal to the gate low potential VGL, and the electric potential of the switch signal XSWR is equal to the gate high potential VGH, the transistors T1 and T3 are both turned on, such that the reset signals MUX_L1 and MUX_L2 are transmitted to the gates of the transistors T2 and T4 respectively. In this case, because the electric potentials of the reset signals MUX_L1 and MUX_L2 are the reset levels Lv2 and Lv1 respectively, biases of the reset levels Lv2 and Lv1 are applied to the respective gates of the transistors T2 and T4, so that the transistors T2 and T4 are not turned on. In this case, voltage drops between the two terminals of the capacitor C1 and between the two terminals of the capacitor C2 are (VGL−Lv2) and (VGL−Lv1) respectively. In addition, during the frame period F[+], when the electric potential of the switch signal SWR is equal to the gate high potential VGH, and the electric potential of the switch signal XSWR is equal to the gate low potential VGL, the transistors T1 and T3 are not turned on; yet the electric potential of the gate of the transistor T2 is increased to (Lv2+VGH−VGL) because of the coupling effect of the capacitor C1, and the electric potential of the gate of the transistor T4 is increased to (Lv1+VGH−VGL) because of the coupling effect of the capacitor C2. As a result, the transistors T2 and T4 are both turned on and the pixel voltage signals S1 and S2 are transmitted to the data lines L1 and L2 respectively; and the electric potentials of the data lines L1 and L2 are the negative polarity pixel voltage +Vp and the positive polarity pixel voltage −Vp respectively. It is clear from the above description that when the transistors T2 and T4 are turned on because of the coupling effect of the capacitors C1 and C2, the voltage differences between the gate of the transistor T2 and the data line L1 and between the gate of the transistor T4 and the data line L2 are (Lv2+VGH−VGL−Vp) and (Lv1+VGH−VGL−Vp) respectively. (Lv1+VGH−VGL−Vp) is equal to the voltage difference ΔV1 shown in
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In this embodiment, the transistors T1 to T12 are all NMOS transistors. The operation manner of the capacitor C3, the transistor T5, and the transistor T6 of the driving unit 110 is similar to that of the capacitor C1, the transistor T1, and the transistor T2; and the operation manner of the capacitor C5, the transistor T9, and the transistor T10 of the driving unit 120 is similar to that of the capacitor C2, the transistor T3, and the transistor T4. What is different is that the operations of the capacitor C1, the transistor T1, and the transistor T2 and the operations of the capacitor C2, the transistor T3, and the transistor T4 are controlled by the switch signals SWR and XSWR, whereas the operations of the capacitor C3, the transistor T5, and the transistor T6 and the operations of the capacitor C5, the transistor T9, and the transistor T10 are controlled by the switch signals SWG and XSWG instead. The rest of the operation manners remain the same. As shown in
Likewise, the operation manner of the capacitor C4, the transistor T7, and the transistor T8 of the driving unit 110 is similar to that of the capacitor C1, the transistor T1, and the transistor T2; and the operation manner of the capacitor C6, the transistor T11, and the transistor T12 of the driving unit 120 is similar to that of the capacitor C2, the transistor T3, and the transistor T4. What is different is that the operations of the capacitor C1, the transistor T1, and the transistor T2 and the operations of the capacitor C2, the transistor T3, and the transistor T4 are controlled by the switch signals SWR and XSWR, whereas the operations of the capacitor C4, the transistor T7, and the transistor T8 and the operations of the capacitor C6, the transistor T11, and the transistor T12 are controlled by the switch signals SWB and XSWB instead. The rest of the operation manners remain the same. As shown in
In an embodiment of the present invention, the data lines L1, L2, L3, L4, L5, and L6 are coupled to the sub-pixels including a red sub-pixel R, a green sub-pixel G, a blue sub pixel B, a red sub-pixel R, a green sub pixel G, and a blue sub-pixel B respectively. Because the pixel voltage signals S1 and S2 received by the data voltage input terminals IN1 and IN2 have different polarities, the display 200 is driven in a column inversion manner through the above circuit structure and connection manner.
In an embodiment of the present invention, the transistors T1 to T12 are all PMOS transistors. As shown in
During the frame period F[+], when the electric potential of the switch signal SWR is equal to the gate high potential VGH, and the electric potential of the switch signal XSWR is equal to the gate low potential VGL, the transistors T1 and T3 in
Similarly, during the frame period F[−], when the electric potential of the switch signal SWR is equal to the gate high potential VGH, and the electric potential of the switch signal XSWR is equal to the gate low potential VGL, the transistors T1 and T3 in
When the transistors T1 to T12 are all PMOS transistors, both the operation manners of the capacitor C3, the transistor T5, and the transistor T6 of the driving unit 110, and of the capacitor C4, the transistor T7, and the transistor T8 of the driving unit 110 can be inferred by referring to the above operation manner of the capacitor C1, the transistor T1, and the transistor T2 in
In an embodiment of the present invention, the driving unit 110 and the driving unit 120 of the multiplexer 100 may be integrated with a cell testing (CT) circuit of the display 200. Please refer to
In another embodiment of the present invention, the driving unit 110 further includes transistors T13, T15, and T16, and the driving unit 120 further includes transistors T14, T17, and T18. The transistors T13 to T18 are all NMOS transistors. The transistor T13 includes a first terminal configured to receive the switch signal SWR, a second terminal coupled to the data line L1, and a control terminal configured to receive the test control signal CT. The transistor T14 includes a first terminal configured to receive the switch signal SWR, a second terminal coupled to the data line L2, and a control terminal configured to receive the test control signal CT. The transistor T15 includes a first terminal configured to receive the switch signal SWG, a second terminal coupled to a data line L3, and a control terminal configured to receive the test control signal CT. The transistor T16 includes a first terminal configured to receive the switch signal SWB, a second terminal coupled to a data line L4, and a control terminal configured to receive the test control signal CT. The transistor T17 includes a first terminal configured to receive the switch signal SWG, a second terminal coupled to a data line L5, and a control terminal configured to receive the test control signal CT. The transistor T18 includes a first terminal configured to receive the switch signal SWB, a second terminal coupled to a data line L6, and a control terminal configured to receive the test control signal CT. When a cell testing is performed on the display 200, the electric potential of the test control signal CT is increased to a high electric potential, so that the transistors T13 and T18 are turned on to transmit the switch signal SWR to the data lines L1 and L2, transmit the switch signal SWG to the data lines L3 and L4, and transmit the switch signal SWB to the data lines L5 and L6. Meanwhile, the transistors T1, T3, T5, T7, T9, and T11 are turned on because of the switch signals XSWR, XSWG, and/or XSWB, such that the transistors T2, T4, T6, T8, T10 and T12 are turned off because the biases of the reset signals MUX_L1 and/or MUX_L2 are being applied to the gates thereof. In other words, when a cell testing is performed on the display 200, the switch signals SWR, SWG, and SWB are used as pixel voltage signals to update the gray level of the sub-pixels of the display 200. In addition, it should be noted that when a cell testing is performed on the display 200, data voltage input terminals IN1 and IN2 stop inputting the pixel voltage signals S1 and S2, so that any interference to the cell testing process can be avoided.
In an embodiment of the present invention, the transistors T1 to T18 in
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Similarly, during the frame period F[−], when the electric potential of the switch signal SWR is equal to the gate low potential VGL, and the electric potential of the switch signal XSWR is equal to the gate high potential VGH, neither the transistor T1 or the transistor T5 in
With reference to
In this embodiment, the transistors T1 to T24 in
Likewise, the operation manner of the transistors T13 to T16 and the capacitor C4 of the driving unit 110 is similar to that of the transistors T1 to T4 and the capacitor C1; and the operation manner of the transistors T21 to T24 and the capacitor C6 of the driving unit 120 is similar to that of the transistors T5 to T8 and the capacitor C2. What is different is that the operations of the transistors T1 to T4 and the capacitor C1 and the operations of the transistors T5 to T8 and the capacitor C2 are controlled by the switch signals SWR and XSWR, whereas the operations of the transistors T13 to T16 and the capacitor C4 and the operations of the transistors T21 to T24 and the capacitor C6 are controlled by the switch signals SWB and XSWB instead. The rest of the operation manners remain the same. As shown
In an embodiment of the present invention, the transistors T1 to T24 in
In an embodiment of the present invention, the driving unit 110 and the driving, unit 120 in
In another embodiment of the present invention, the driving unit 110 in
In an embodiment of the present invention, the transistors T1 to T30 in
Through the above embodiments, two different reset signals are applied to the multiplexer of the present invention to increase an absolute value of a voltage difference between a gate and a drain of a transistor for driving a data line, thereby strengthening the driving capability of the transistor. In this way, no matter whether the transistors of the multiplexer are NMOS transistors or PMOS transistors, the multiplexer has a sufficient driving capability for data lines and sub-pixels. Therefore, the transistors of the multiplexer can all be N-Metal-Oxide-Semiconductor transistors or P-Metal-Oxide-Semiconductor transistors, thereby simplifying the process of manufacturing the multiplexer and/or a panel and improving the competitiveness of products thereof.
The above description wily provides preferred embodiments of the present invention, and all equivalent changes and modifications made according to the claims of the present invention falls within the scope of the present invention.
Claims
1. A multiplexer, comprising:
- a plurality of first driving units, each of the first driving units comprising: a first data voltage input terminal, for receiving a first pixel voltage signal; a first capacitor, comprising; a first terminal, for receiving a first switch signal; and a second terminal; a first transistor, comprising: a first terminal, coupled to the second terminal of the first capacitor; a second terminal, for receiving a first reset signal; and a control terminal, for receiving a second switch signal; wherein the first switch signal and the second switch signal have opposite phases; and a second transistor, comprising: a first terminal, coupled to the first data voltage input terminal; a second terminal, coupled to a first data line; and a control terminal, coupled to the second terminal of the first capacitor; and
- a plurality of second driving units, each of the second driving units comprising: a second data voltage input terminal, for receiving a second pixel voltage signal, wherein the first pixel voltage signal and the second pixel voltage signal have opposite polarities; a second capacitor, comprising: a first terminal, coupled to the first terminal of the first capacitor, and is for receiving the first switch signal; and a second terminal; a third transistor, comprising: a first terminal, coupled to the second terminal of the second capacitor; a second terminal, for receiving a second reset signal; and a control terminal, coupled to the control terminal of the first transistor, for receiving the second switch signal; and a fourth transistor, comprising: a first terminal, coupled to the second data voltage input terminal; a second terminal, coupled to a second data line; and a control terminal, coupled to the second terminal of the second capacitor;
- wherein the first reset signal is different from the second reset signal.
2. The multiplexer according to claim 1, wherein
- each of the first driving units further comprises: a third capacitor, comprising: a first terminal, for receiving a third switch signal; and a second terminal; a fifth transistor, comprising: a first terminal, coupled to the second terminal of the third capacitor; a second terminal, for receiving the first reset signal; and a control terminal, for receiving a fourth switch signal; wherein the third switch signal and the fourth switch signal have opposite phases; a sixth transistor, comprising: a first terminal, coupled to the first data voltage input terminal; a control terminal, coupled to the second terminal of the third capacitor; and a second terminal, coupled to a third data line; a fourth capacitor, comprising: a first terminal, for receiving a fifth switch signal; and a second terminal; a seventh transistor, comprising: a first terminal, coupled to the second terminal of the fourth capacitor; a second terminal, for receiving the first reset signal; and a control terminal, for receiving a sixth switch signal, wherein the fifth switch signal and the sixth it signal have opposite phases; and an eighth transistor, comprising: a first terminal, coupled to the first data voltage input terminal; a control terminal, coupled to the second terminal of the fourth capacitor; and a second terminal, coupled to a fourth data line;
- each of the second driving units further comprises: a fifth capacitor, comprising: a first terminal, coupled to the first terminal of the third capacitor, for receiving the third switch signal; and a second terminal; a ninth transistor, comprising: a first terminal, coupled to the second terminal of the fifth capacitor; a second terminal, for receiving the second reset signal; and a control terminal, coupled to the control terminal of the fifth transistor, for receiving the fourth switch signal; a tenth transistor, comprising: a first terminal, coupled to the second data voltage input terminal; a control terminal, coupled to the second terminal of the fifth capacitor; and a second terminal, coupled to a fifth data line; a sixth capacitor, comprising: a first terminal, coupled to the first terminal of the fourth capacitor, for receiving the fifth switch signal; and a second terminal; an eleventh transistor, comprising: a first terminal, coupled to the second terminal of the sixth capacitor; a second terminal, for receiving the second reset signal; and a control terminal, coupled to the control terminal of the seventh transistor, for receiving the sixth switch signal; and a twelfth transistor, comprising: a first terminal, coupled to the second data voltage input terminal; a control terminal, coupled to the second terminal of the sixth capacitor; and a second terminal, coupled to a sixth data line.
3. The multiplexer according to claim 1, wherein
- each of the first driving units further comprises: a thirteenth transistor, comprising: a first terminal, for receiving the first switch signal; a second terminal, coupled to the first data line; and a control terminal, for receiving a test control signal; and
- each of the second driving units further comprises: a fourteenth transistor, comprising: a first terminal, for receiving the first switch signal; a second terminal, coupled to the second data line; and a control terminal, for receiving the test control signal.
4. The multiplexer according to claim 2, wherein
- each of the first driving units further comprises: a thirteenth transistor, comprising: a first terminal, for receiving the first switch signal; a second terminal, coupled to the first data line; and a control terminal, for receiving a test control signal; a fifteenth transistor, comprising: a first terminal, for receiving the third switch signal; a second terminal, coupled to the third data line; and a control terminal, for receiving the test control signal; and a sixteenth transistor, comprising: a first terminal, for receiving the fifth switch signal; a second terminal, coupled to the fourth data line; and a control terminal, for receiving the test control signal; and
- each of the second driving units further comprises: a fourteenth transistor, comprising: a first terminal, for receiving the first switch signal; a second terminal, coupled to the second data line; and a control terminal, for receiving the test control signal; a seventeenth transistor, comprising: a first terminal, for receiving the third switch signal; a second terminal, coupled to the fifth data line; and a control terminal, for receiving the test control signal; and an eighteenth transistor, comprising: a first terminal, for receiving the fifth switch signal; a second terminal, coupled to the sixth data line; and a control terminal, for receiving the test control signal.
5. A multiplexer, comprising:
- a plurality of first driving units, each of the first driving units comprising: a first data voltage input terminal, for receiving a first pixel voltage signal; a first transistor, comprising: a first terminal, for receiving a first system voltage; a second terminal; and a control terminal, for receiving a first switch signal; a second transistor, comprising: a first terminal, coupled to the second terminal of the first transistor; a second terminal, for receiving a second system voltage; and a control terminal, for receiving a second switch signal, wherein the first switch signal and the second switch signal have opposite phases; a third transistor, comprising: a first terminal, coupled to the first data voltage input terminal; a second terminal, coupled to a first data line; and a control terminal; a fourth transistor, comprising: a first terminal, coupled to the control terminal of the third transistor; a second terminal, for receiving a first reset signal; and a control terminal, for receiving the second switch signal; and a first capacitor, comprising: a first terminal, coupled to the second terminal of the first transistor and the first terminal of the second transistor; and a second terminal, coupled to the control terminal of the third transistor and the first terminal of the fourth transistor; and
- a plurality of second driving units, each of the second driving units comprising: a second data voltage input terminal, for receiving a second pixel voltage signal, wherein the first pixel voltage signal and the second pixel voltage signal have opposite polarities; a fifth transistor, comprising: a first terminal, for receiving the first system voltage; a second terminal; and a control terminal, for receiving the first switch signal; a sixth transistor, comprising: a first terminal, coupled to the second terminal of the fifth transistor; a second terminal, for receiving the second system voltage; and a control terminal, for receiving the second switch signal; a seventh transistor, comprising: a first terminal, coupled to the second data voltage input terminal; a second terminal, coupled to a second data line; and a control terminal; an eighth transistor, comprising: a first terminal, coupled to the control terminal of the seventh transistor; a second terminal, for receiving a second reset signal; and a control terminal, for receiving the second switch signal; and a second capacitor, comprising: a first terminal, coupled to the second terminal of the fifth transistor and the first terminal of the sixth transistor; and a second terminal, coupled to the control terminal of the seventh transistor and the first terminal of the eighth transistor;
- wherein the first reset signal is different from the second reset signal.
6. The multiplexer according to claim 5, wherein
- each of the first driving units further comprises: a ninth transistor, comprising: a first terminal, for receiving the first system voltage; a second terminal; and a control terminal, for receiving a third switch signal; a tenth transistor, comprising: a first terminal, coupled to the second terminal of the ninth transistor; second terminal, for receiving the second system voltage; and a control terminal, for receiving a fourth switch signal; wherein the third switch signal and the fourth switch signal have opposite phases; an eleventh transistor, comprising; a first terminal coupled to the first data voltage input terminal; a second terminal, coupled to a third data line; and a control terminal; a twelfth transistor, comprising: a first terminal, coupled to the control terminal of the eleventh transistor; a second terminal, for receiving the first reset signal; and a control terminal, for receiving the fourth switch signal; a third capacitor, comprising: a first terminal, coupled to the second terminal of the ninth transistor and the first terminal of the tenth transistor; and a second terminal, coupled to the control terminal of the eleventh transistor and the first terminal of the twelfth transistor; a thirteenth transistor, comprising: a first terminal, for receiving the first system voltage; a second terminal; and a control terminal, for receiving a fifth switch signal; a fourteenth transistor, comprising: a first terminal, coupled to the second terminal of the thirteenth transistor; a second terminal, for receiving the second system voltage; and a control terminal, for receiving a sixth switch signal; wherein the fifth switch signal and the sixth switch signal have opposite phases; a fifteenth transistor, comprising: a first terminal, coupled to the first data voltage input terminal; a second terminal, coupled to a fourth data line; and a control terminal; a sixteenth transistor, comprising: a first terminal, coupled to the control terminal of the fifteenth transistor; a second terminal, for receiving the first reset signal; and a control terminal, for receiving the sixth switch signal; and a fourth capacitor, comprising: a first terminal, coupled to the second terminal of the thirteenth transistor and the first terminal of the fourteenth transistor; and a second terminal, coupled to the control terminal of the fifteenth transistor and the first terminal of the sixteenth transistor;
- each of the second driving units further comprises: a seventeenth transistor, comprising a first terminal, for receiving the first system voltage; a second terminal; and a control terminal, for receiving the third switch signal; an eighteenth transistor, comprising: a first terminal, coupled to the second terminal of the seventeenth transistor; a second terminal, for receiving the second system voltage; and a control terminal, for receiving the fourth switch signal; a nineteenth transistor, comprising: a first terminal, coupled to the second data voltage input terminal; a second terminal, coupled to a fifth data line; and a control terminal; a twentieth transistor, comprising: a first terminal, coupled to the control terminal of the nineteenth transistor; a second terminal, for receiving the second reset signal; and a control terminal, for receiving the fourth switch signal; a fifth capacitor, comprising: a first terminal, coupled to the second terminal of the seventeenth transistor and the first terminal of the eighteenth transistor; and
- a second terminal, coupled to the control terminal of the nineteenth transistor and the first terminal of the twentieth transistor; a twenty-first transistor, comprising: a first terminal, for receiving the first system voltage; a second terminal; and a control terminal, for receiving the fifth switch signal; a twenty-second transistor, comprising: a first terminal, coupled to the second terminal of the twenty-first transistor; a second terminal, for receiving the second system voltage; and a control terminal, for receiving the sixth switch signal; a twenty-third transistor, comprising: a first terminal, coupled to the second data voltage input terminal; a second terminal, coupled to a sixth data line; and a control terminal; a twenty-fourth transistor, comprising: a first terminal, coupled to the control terminal of the twenty-third transistor; a second terminal for receiving the second reset signal; and a control terminal, for receiving the sixth switch signal; and a sixth capacitor, comprising: a first terminal, coupled to the second terminal of the twenty-first transistor and the first terminal of the twenty-second transistor; and a second terminal, coupled to the control terminal of the twenty-third transistor and the first terminal of the twenty-fourth transistor.
7. The multiplexer according to claim 5, wherein
- each of the first driving units further comprises: a twenty-fifth transistor, comprising: a first terminal, for receiving the first switch signal; a second terminal, coupled to the first data line; and a control terminal, for receiving a test control signal; and
- each of the second driving units further comprises: a twenty-sixth transistor, comprising: a first terminal, for receiving the first switch signal; a second terminal, coupled to the second data line; and a control terminal, for receiving the test control signal.
8. The multiplexer according to claim 6, wherein
- each of the first driving units further comprises: a twenty-fifth transistor, comprising: a first terminal, for receiving the first switch signal; a second terminal, coupled to the first data line; and a control terminal, for receiving a test control signal; a twenty-seventh transistor, comprising: a first terminal, for receiving the third switch signal; a second terminal, coupled to the third data line; and a control terminal, for receiving the test control signal; and a twenty-eighth transistor, comprising: a first terminal, for receiving the fifth switch signal; a second terminal, coupled to the fourth data line; and a control terminal, for receiving the test control signal; and
- each of the second driving units further comprises: a twenty-sixth transistor, comprising: a first terminal, for receiving the first switch signal; a second terminal, coupled to the second data line; and a control terminal, for receiving the test control signal; a twenty-ninth transistor, comprising: a first terminal, for receiving the third switch signal; a second terminal, coupled to the fifth data line; and a control terminal, for receiving, the test control signal; and a thirtieth transistor, comprising: a first terminal, for receiving the fifth switch signal; a second terminal, coupled to the sixth data line; and a control terminal, for receiving the test control signal.
9. The multiplexer according to claim 1, wherein all the transistors of the first driving unit and the second driving unit are N-type metal-oxide-semiconductor transistors.
10. The multiplexer according to claim 5, wherein all the transistors of the first driving unit and the second driving unit are P-type metal-oxide-semiconductor transistors.
11. The multiplexer according to claim 1, wherein the multiplexer is for a display, and during a Nth frame period of the display, an electric potential of the first reset signal is higher than the electric potential of the second reset signal, and N is a positive integer; and
- wherein during the (N+1)th frame period of the potential of the first reset signal is lower than the electric potential of the second reset signal.
12. The multiplexer according to claim 2, wherein the fifth data line is between the first and the fourth data lines, the fourth data line is between the fifth and the second data lines, the second data line is between the fourth and the third data lines, and the third data line is between the second and the sixth data lines.
13. A method for driving the multiplexer according to claim 1, wherein the multiplexer is used for a display, and all the transistors of the first driving unit and the second driving unit are N-type metal-oxide-semiconductor transistors, the method comprising:
- during the nth frame period of the display, making the first pixel voltage signal to have a first polarity, making the second pixel voltage signal to have a second polarity, making the first reset signal to have an electric potential at a first reset level, and making the second reset signal to have an electric potential at a second reset level, wherein n is a positive integer, the first polarity is different from the second polarity, and the second reset level is lower than the first reset level; and
- during the (n+1)th frame period of the display, making the first pixel voltage signal to have the second polarity, making the second pixel voltage signal to have the first polarity, making the first reset signal to have the electric potential at the second reset level, and making the second reset signal to have the electric potential at the first reset level.
14. The method according to claim 13, wherein the method further comprises:
- setting the first reset level to be lower than a ground potential.
15. The method according to claim 14, wherein the method further comprises:
- making a voltage difference between the ground potential and the first reset level to be equal to a preset voltage difference, wherein the preset voltage difference is between Vth+0.5 V and Vth−0.5 V, and Vth being an average value of threshold voltages of all the transistors in the first driving unit and the transistor second driving unit.
16. The method according to claim 13, wherein the first switch signal and the second switch signal are respective square waves having electric potentials switched between gate high potential and a gate low potential, and the second reset level equals to the gate low potential.
17. A method for driving the multiplexer according to claim 5, wherein the multiplexer is used for a liquid crystal display, and all the transistors of the first driving unit and the second driving unit are P-type metal-oxide-semiconductor transistors, the method comprising:
- during the nth frame period of the liquid crystal display, making the first pixel voltage signal to have a first polarity, making the second pixel voltage signal to have a second polarity, making the first reset signal to have an electric potential at a first reset level, and taking the second reset signal to have an electric potential at a second reset level, wherein n is a positive integer, the first polarity is different from the second polarity, and the second reset level is higher than the first reset level; and
- during the (n+1)th frame period of the liquid crystal display, making the first pixel voltage signal to have the second polarity, making the second pixel voltage signal to have the first polarity, making the first reset signal to have the electric potential at the second reset level, and making the second reset signal to have the electric potential at the first reset level.
18. The method according to claim 17, wherein the method further comprises:
- setting the first reset level to be higher than a ground potential.
19. The method according o claim 18, wherein the method further comprises:
- making a voltage difference between the first reset level and the ground potential to be equal to a preset voltage difference, wherein the preset voltage difference is between Vth+0.5 V and Vth−0.5 V, and Vth being an average value of absolute values of threshold voltages of all the transistors in the first driving unit and the second driving unit.
20. The method according to claim 17, wherein the first switch signal and the second switch signal are respective square waves having electric potentials switched between a gate high potential and a gate low potential, and the second reset level is equal to the gate high potential.
Type: Application
Filed: Feb 21, 2017
Publication Date: Aug 24, 2017
Patent Grant number: 10559274
Inventors: Peng-Bo XI (HSIN-CHU), Sung-Yu SU (HSIN-CHU)
Application Number: 15/437,589